scholarly journals Numerical Simulation of Depth Tracking Control of an Underwater Towed System Coupled with Wave–Ship Interference

2021 ◽  
Vol 9 (8) ◽  
pp. 874
Author(s):  
Xianyuan Yang ◽  
Jiaming Wu ◽  
Quanlin Li ◽  
Haiyan Lv
Keyword(s):  
Numerical Simulation ◽  
Control System ◽  
Tracking Control ◽  
Stokes Equations ◽  
Numerical Study ◽  
Fluid Motion ◽  
System A ◽  
Head Waves ◽  
Longitudinal Position ◽  
Mesh Technique

This paper presents a numerical study of the depth tracking control for an underwater towed system under wave–ship interference condition. To overcome the laminations of ignoring the hydrodynamic factors and wave–ship interference in the existing simulation model for the depth tracking operation of the underwater towed system, a numerical model combining the control system with the computational fluid dynamics (CFD) method based on the overset mesh technique is explored and constructed; the influence of towing ship and head waves is introduced into the numerical analysis of the underwater towed system; a depth control system based on the center of gravity adjustment is proposed and its control characteristics are discussed. The fluid motion around the towed vehicle and the towing ship is governed by the Navier–Stokes equations, and the overset mesh technique is applied for the numerical solution of the equations. The towing cable connecting the towed vehicle and towing ship is governed by the quasi-steady-state catenary equations. The depth tracking controller adjusting the longitudinal position of a shifting weight is constructed based on the proportional–integral–derivative (PID) algorithm. The simulation results show that the numerical simulation system is practicable, and the depth tracking control system is feasible, effective, and robust.

The spin-up from rest of a fluid-filled torus

1994 ◽  
Vol 265 ◽  
pp. 217-244 ◽  
Author(s):  
F. N. Madden ◽  
T. Mullin
Keyword(s):  
Rotation Rate ◽  
Control Parameter ◽  
Stokes Equations ◽  
Numerical Study ◽  
Fluid Motion ◽  
Navier Stokes ◽  
Transient Phase ◽  
Navier Stokes Equations ◽  
Novel Variant ◽  
Transition Points

We present the results of an experimental and numerical study of the spin-up from rest to solid-body rotation of a fluid-filled torus. In separate experiments, the rotation rate of the container is suddenly increased to a fixed value and the final rotation rate is used to define a non-dimensionalized control parameter, C. At low values of C, the observed flows during the transient phase are axisymmetric and spin-up is achieved through viscous diffusion. This in turn is followed by significant secondary flow and the appearance of ‘fronts’ as C is increased. During the transient phase the fluid motion near the inner wall of the container is dynamically unstable according to Rayleigh's criterion. Thus at higher values of C wave-like structures break the axisymmetry, non-uniqueness in the details of the process is found and finally, an innear wall instability is observed directly. A plot of the spin-up time versus C shows breaks in the slope at transition points between each of the above dynamical regimes but the overall trend is found to be insensitive to the details of the fluid motion. Further elucidation of the dynamical processes is provided by a novel variant of the now standard phase-space reconstruction techniques. The results show a systematic splitting of the phase paths as C is increased.Finally, in the complementary numerical study, the time-dependent Navier–Stokes equations are solved for axisymmetric flows. Here, the flow is computed using a velocity–streamfunction–vorticity formulation in a two-dimensional plane with a velocity component normal to this plane. The quantitative and qualitative agreement between the numerical and experimental results is excellent for moderate values of the dynamical control parameter C.

scholarly journals Improving the mathematical stability in the numerical simulation of the vehicle movement with an electronic movement control system

2021 ◽  
Vol 2061 (1) ◽  
pp. 012092
Author(s):  
E V Balakina ◽  
D S Sarbaev ◽  
I V Sergienko
Keyword(s):  
Numerical Simulation ◽  
Control System ◽  
Movement Control ◽  
Turning Angle ◽  
Surface Change ◽  
Hard Surface ◽  
System A ◽  
Vehicle Movement

Abstract The aim of the study is to determine the influence of the calculated radius type on the calculated parameters of the vehicle movement, equipped with an electronic movement control system. A numerical simulation of the vehicle movement equipped with an electronic movement control system was carried out. Under calculated conditions, there are forces that disrupt the stable and controlled vehicle movement. The studies carried out have shown that in the numerical simulation of the parameters of the vehicle movement, the use of a dynamic radius instead of a rolling radius never affects the calculated values of the vehicle’s longitudinal shifts. In this case, the values of the lateral shifts and the turning angle of the vehicle on a dry hard surface change insignificantly, but there is a significant mathematical instability of the solution. On a wet hard surface, the influence of the calculated radii types on the characteristics of the simulated vehicle movement is preserved, but this influence is less pronounced.

scholarly journals Numerical Simulation of Damage in Sandwich Composite Panels Due to Hydrodynamic Impact

2021 ◽  
Vol 53 (3) ◽  
pp. 210304
Author(s):  
Satrio Wicaksono ◽  
Nur Ridhwan Muharram ◽  
Hermawan Judawisastra ◽  
Tatacipta Dirgantara
Keyword(s):  
Numerical Simulation ◽  
Numerical Study ◽  
Fluid Motion ◽  
Real Life ◽  
Damage Mechanism ◽  
Composite Panel ◽  
Sandwich Composite ◽  
Composite Panels ◽  
Hydrodynamic Load ◽  
Hydrodynamic Impact

The float and hull are vital parts of amphibious planes and boats, respectively, as both have to absorb hydrodynamic impact due to interaction with water. Sandwich composite panels are commonly used for such applications and other impact-absorbing structures. Unfortunately, the failure mechanism of sandwich composite panels under hydrodynamic impact is very complicated, as it may consist of composite skin failure, core failure, and non-uniform delamination. Hence, a numerical study on the damage of sandwich composite panels under hydrodynamic load is necessary. In this study, numerical simulation implementing the Coupled Eulerian-Lagrangian (CEL) method was performed to observe the damage mechanism of sandwich composite panels. The CEL method combines the Lagrangian and Eulerian frames into one model. Thus, analysis of structure deformation and fluid motion can be performed simultaneously. The result of the current numerical simulation shows a fair agreement with the experimental results in the literature, which shows that the current methodology can represent the sandwich composite panel response in real-life conditions, especially before shear core failure initiates.

scholarly journals Tracking Control for an Electro-Hydraulic Rotary Actuator Using Fractional Order Fuzzy PID Controller

Electronics ◽  
2020 ◽  
Vol 9 (6) ◽  
pp. 926 ◽  
Author(s):  
Tri Cuong Do ◽  
Duc Thien Tran ◽  
Truong Quang Dinh ◽  
Kyoung Kwan Ahn
Keyword(s):  
Fuzzy Logic ◽  
Control System ◽  
Fractional Order ◽  
Tracking Control ◽  
Trajectory Tracking Control ◽  
Integer Order ◽  
Fuzzy Pid Controller ◽  
System A ◽  
Rotary Actuator ◽  
Fractional Order Pid

This paper presents a strategy for a fractional order fuzzy proportional integral derivative controller (FOFPID) controller for trajectory-tracking control of an electro-hydraulic rotary actuator (EHRA) under variant working requirements. The proposed controller is based on a combination of a fractional order PID (FOPID) controller and a fuzzy logic system. In detail, the FOPID with extension from the integer order to non-integer order of integral and derivative functions helps to improve tracking, robustness and stability of the control system. A fuzzy logic control system is designed to adjust the FOPID parameters according to time-variant working conditions. To evaluate the proposed controller, co-simulations (using AMESim and MATLAB) and real-time experiments have been conducted. The results show the effectiveness of the proposed approach compared to other typical controllers.

The Experiment of Trajectory Tracking Control of Joint Manipulator with PC-Based

2011 ◽  
Vol 101-102 ◽  
pp. 431-434
Author(s):  
Mei Qin Zhang ◽  
Wu Feng ◽  
Hui Di Zhang ◽  
Xian Chen Wang
Keyword(s):  
Control System ◽  
Tracking Control ◽  
Robot Control ◽  
Control Program ◽  
High Price ◽  
Trajectory Tracking Control ◽  
System A ◽  
The Poor ◽  
Articulated Robot ◽  
Robot Control System

For the disadvantages of the poor open and high price of the special joint robot control system, a general PC-based three degree articulated robot control system is proposed. After modeling kinematics of the robot, the kinematics trajectory is planned and the trajectory algorithm is designed in a given error condition. Finally, the control program is done with VB, and it is verified by an example.

scholarly journals Tracking control of an underactuated rigid body with a coupling input force

2014 ◽  
Vol 24 (3) ◽  
pp. 321-332 ◽  
Author(s):  
Sebastian Korczak
Keyword(s):  
Numerical Simulation ◽  
Rigid Body ◽  
Tracking Control ◽  
Tracking Problem ◽  
State Variables ◽  
Input Force ◽  
System A ◽  
Coupling Force ◽  
Lie Brackets ◽  
Computed Torque

Abstract This paper presents a set of basic problems concerning the control of an underactuated dynamic system. Exemplary system of a planar rigid body with a coupling input force is described. Lie brackets method is used to show accessibility of the system. A tracking problem is solved with computed torque algorithm. The coupling force makes the convergence to zero of all state variables errors impossible. After numerical simulation, stability of the system is mentioned

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